We decided early on with Red Morning Press that the copyrights of a work would remain with our authors. That's rarely (if ever) an option with the huge publishing conglomerates. We assume that if we do a good job of caring for our authors, they'll want to publish with us again. If they suddenly become famous and their books are in hyper-demand, they have the option to get another press to publish it. If you believe, as we do, that the copyrights are the most valuable asset an author owns, then it's hard to swallow that so many authors give them away for virtually nothing.
The relationship between copyright/trademark/patent laws and creativity is something that fascinates me. On one hand, the laws can be overly protective. On the other, they can be the only protection an artist has. One deviation from the often black-and-white discussions about copyright--especially as they pertain to music--can be found at the Creative Commons web site. The idea here is that you can share some of your rights without giving them all away.